1. Field of the Invention
The present invention relates to a gas turbine engine, and more particularly, to the cooling of hollow blades for turbines in such engines.
2. Description of the Prior Art
In the manufacture of blades for turbines, it has been customary in recent years to include a hollow passageway in each blade, arranged in a serpentine fashion, for the purpose of passing a cooling fluid, such as air, so as to cool the blade. The inlet of air and the first section of passageway is arranged adjacent and parallel to the leading edge of the blade which may be the hottest portion of the blade. It has also been suggested to provide chordwise ribs spaced longitudinally of the passageway for promoting turbulence in the adjacent coolant boundary layer, thereby increasing the convective heat transfer coefficient. Such ribs were described in U.S. Pat. No. 3,628,885, Sidenstick et al, issued Dec. 21, 1971 to General Electric Company. These ribs extend at right angles to the axis of the passageway.